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This paper aims to offer the aerodynamic testing community a new procedure for manufacturing high-quality aerodynamic probes suitable for 3D flow measurements with consistent geometry and calibration by taking advantage of the additive manufacturing technology.

The design methodology combines the advantages and flexibilities of computer aided design (CAD)/computer aided manufacturing (CAM) along with the use of computational fluid dynamics to design and analyse suitable probe shapes prior to manufacturing via rapid prototyping.

A viable procedure to design and possibly batch manufacture geometrically accurate pneumatic probes with consistent calibration is shown to be possible through this work. Multi-jet modelling prototyping methods with wax-based support materials are found to be a cost-effective method when clean and long sub-millimetre pressure channels are to be cut.

Utilisation of the geometry consistency that is made possible by 3D printing technology for the design and development of pneumatic probes is described. It is suggested that the technique could lead to batch production of identical probes, thus avoiding precious time of a skilled labourer and elaborate individual calibration requirement.

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming and powder metallurgy are briefly discussed. The range of applications of finite elements on the subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for the last five years, and more than 1100 references are listed.

The purpose of this paper is to predict pressure pulsation in Kaplan hydraulic turbines.

State of the art numerical simulation techniques are employed to simulate three‐dimensional flows in the whole flow passage of a Kaplan turbine so that pressure pulsations can be computed in both time domain and frequency domain. Numerical results are verified by experiments carried out on the most advanced experimental platform in China.

It is found that the proposed numerical model is a viable tool for prediction of pressure pulsations. The simulation shows that the model turbine and prototype turbine have the same pressure pulsation frequencies and rotating frequencies and the same transmission patterns under similar operation conditions. However, there is no similarity for the amplitude of the pressure pulsation between the model turbine and the prototype turbine. Therefore pressure pulsations in a prototype turbine cannot be obtained by scaling the experimental results of the model turbine using a similarity relationship.

The findings will be very valuable for the design of hydraulic turbines and large‐scale hydraulic power stations.

The proposed numerical method provides a viable tool for hydraulic turbine and power station designers to predict the pressure pulsations in prototype turbines. It is a useful tool to help improve the performance of hydraulic turbines. The findings made in the numerical simulation have been verified by experiments, which is also a valuable reference for hydraulic turbine designers.

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.

This study aims to present the numerical study on supersonic jet mixing characteristics of the co-flow jet by varying lip thickness (LT). The LT chosen for the study is 2 mm, 7.75 mm and 15 mm.

The primary nozzle is designed for delivering Mach 2.0 jet, whereas the secondary nozzle is designed for delivering Mach 1.6 jet. The Nozzle pressure ratio chosen for the study is 3 and 5. To study the mixing characteristics of the co-flow jet, total pressure and Mach number measurements were taken along and normal to the jet axis. To validate the numerical results, the numerical total pressure values were also compared with the experimental result and it is proven to have a good agreement.

The results exhibit that, the 2 mm lip is shear dominant. The 7.75 mm and 15 mm lip is wake dominant. The jet interaction along the jet axis was also studied using the contours of total pressure, Mach number, turbulent kinetic energy and density gradient. The radial Mach number contours at the various axial location of the jet was also studied.

The effect of varying LT in exhaust nozzle plays a vital role in supersonic turbofan aircraft.

Supersonic co-flowing jet mixing effectiveness by varying the LT between the primary supersonic nozzle and the secondary supersonic nozzle has not been analyzed in the past.

This bibliography is offered as a practical guide to published papers, conference proceedings papers and theses/dissertations on the finite element (FE) and boundary element (BE) applications in different fields of biomechanics between 1976 and 1991. The aim of this paper is to help the users of FE and BE techniques to get better value from a large collection of papers on the subjects. Categories in biomechanics included in this survey are: orthopaedic mechanics, dental mechanics, cardiovascular mechanics, soft tissue mechanics, biological flow, impact injury, and other fields of applications. More than 900 references are listed.

The detailed flow behaviour around a four—hole Cobra Pitot pressure probe, developed by the Commonwealth Scientific and Industrial Research Organization, Australia, (CSIRO), to determine the pressure and the velocity components in three dimensional single‐phase/multi‐phase fluid flow, is investigated computationally. The incompressible steady state Navier—Stokes equations are solved numerically using a general purpose computational fluid dynamics (CFD) code developed at CANCES. Computational results are presented for representative probe pitch and yaw angles at a Reynolds number = 2 × 10³, emphasising the pressure distribution and flow separation patterns on the probe tip adjacent to the pressure ports. Quantitative comparison of the computational simulation to experimental results is done by comparing experimental calibration data to numerically computed pressure responses. The topological features of the near tip flow behaviour are visualised using critical point concepts and three dimensional streamlines. Additional qualitative comparison to experiment is discussed using data from a preliminary experimental investigation using surface oil film visualisation techniques, where available. Conclusions are drawn concerning the near tip flow behaviour, the good level of agreement between the numerical results and experimental data and the effectiveness of using a computational analysis to provide accurate detail useful for engineering design purposes.

The purpose of this paper is to numerically study inflow turbulence effects on the transitional flow in a high pressure linear transonic turbine at the design incidence.

The three‐dimensional (3‐D) compressible turbulent flow in a turbine inlet guide vane is simulated using a finite volume based fluid solver coupled with dynamic large eddy simulation (LES) computations to investigate the effects of varying inflow turbulence length scale and the turbulence intensity on the aero‐thermal flow characteristics and the laminar‐turbulent transition phenomena. The computational analyses are extended to very high exit Reynolds number flow conditions to further study the effect of high exit Reynolds numbers on the transitional behavior of the present flow around the inlet guide vane cascades of the turbine. The calculations are performed with varying degree of inflow turbulence intensity values ranging from 0.8 to 6 percent and the inflow turbulence length scales ranging from one to five percent of pitch for different exit isentropic Mach and Reynolds numbers.

The numerical predictions in comparison with the experimental data demonstrate that the level of inflow turbulence closure provided by the present LES computations offers a reliable framework to predict complex turbulent flow and transition phenomena in high free‐stream turbulence environments of high pressure linear turbines.

This is the first instance in which both artificially modified random flow generation method in association with the dynamic procedure of LES application is employed to represent the realistic inflow turbulence conditions in the high pressure turbine and to resolve the transitional flow in a dynamic approach.

A 3‐D eddy current code, TRIFOU, has been used to simulate eddy currents flowing around cracks in very thick conductors, which is a fully 3‐D situation. The measurement set and the probe have also been simulated so that we can compare numerical and experimental output signals. Storage and CPU‐time requirements are detailed and the expectations of such a program in non‐destructive testing are discussed.

This study aims to feature the application of the artificial compressibility method (ACM) for the numerical prediction of two-dimensional (2D) axisymmetric swirling flows.

The respective academic numerical solver, named IGal2D, is based on the axisymmetric Reynolds-averaged Navier–Stokes (RANS) equations, arranged in a pseudo-Cartesian form, enhanced by the addition of the circumferential momentum equation. Discretization of spatial derivative terms within the governing equations is performed via unstructured 2D grid layouts, with a node-centered finite-volume scheme. For the evaluation of inviscid fluxes, the upwind Roe’s approximate Riemann solver is applied, coupled with a higher-order accurate spatial reconstruction, whereas an element-based approach is used for the calculation of gradients required for the viscous ones. Time integration is succeeded through a second-order accurate four-stage Runge-Kutta method, adopting additionally a local time-stepping technique. Further acceleration, in terms of computational time, is achieved by using an agglomeration multigrid scheme, incorporating the full approximation scheme in a V-cycle process, within an efficient edge-based data structure.

A detailed validation of the proposed numerical methodology is performed by encountering both inviscid and viscous (laminar and turbulent) swirling flows with axial symmetry. IGal2D is compared against the commercial software ANSYS fluent – by using appropriate metrics and characteristic flow quantities – but also against experimental measurements, confirming the proposed methodology’s potential to predict such flows in terms of accuracy.

This study provides a robust methodology for the accurate prediction of swirling flows by combining the axisymmetric RANS equations with ACM. In addition, a detailed description of the convective flux Jacobian is provided, filling a respective gap in research literature.